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1.
Ann Bot ; 133(1): 73-92, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-37952103

RESUMO

BACKGROUND AND AIMS: Changes in kelp abundances on regional scales have been highly variable over the past half-century owing to strong effects of local and regional drivers. Here, we assess patterns and dominant environmental variables causing spatial and interspecific variability in kelp persistence and resilience to change in Nova Scotia over the past 40 years. METHODS: We conducted a survey of macrophyte abundance at 251 sites spanning the Atlantic coast of Nova Scotia from 2019 to 2022. We use this dataset to describe spatial variability in kelp species abundances, compare species occurrences to surveys conducted in 1982 and assess changes in kelp abundance over the past 22 years. We then relate spatial and temporal patterns in abundance and resilience to environmental metrics. KEY RESULTS: Our results show losses of sea urchins and the cold-tolerant kelp species Alaria esculenta, Saccorhiza dermatodea and Agarum clathratum in Nova Scotia since 1982 in favour of the more warm-tolerant kelps Saccharina latissima and Laminaria digitata. Kelp abundances have increased slightly since 2000, and Saccharina latissima and L. digitata are widely abundant in the region today. The highest kelp cover occurs on wave-exposed shores and at sites where temperatures have remained below thresholds for growth (21 °C) and mortality (23 °C). Moreover, kelp has recovered from turf dominance following losses at some sites during a warm period from 2010 to 2012. CONCLUSIONS: Our results indicate that dramatic changes in kelp community composition and a loss of sea urchin herbivory as a dominant driver of change in the system have occurred in Nova Scotia over the past 40 years. However, a broad-scale shift to turf-dominance has not occurred, as predicted, and our results suggest that resilience and persistence are still a feature of kelp forests in the region despite rapid warming over the past several decades.


Assuntos
Algas Comestíveis , Kelp , Laminaria , Resiliência Psicológica , Animais , Florestas , Ouriços-do-Mar , Oceanos e Mares , Ecossistema
2.
J Phycol ; 60(3): 685-694, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38548387

RESUMO

Seaweed aquaculture, particularly kelp farming, is a popular topic as a potential solution for mitigating anthropogenic pollutants and enhancing coastal drawdown of carbon and nitrogen. Using a common garden approach, this study evaluated nutrient drawdown capacities of Alaria marginata (ribbon kelp) and Saccharina latissima (sugar kelp) across four commercial kelp farms in Southeast and Southcentral Alaska. Our findings show that A. marginata exhibited ~30% more carbon and 21% more nitrogen content compared to S. latissima. These results demonstrate the potential for A. marginata to serve as a more efficient species for nutrient drawdown into farmed kelp tissues (per unit biomass) for consideration of potential mitigative actions. The efficacy of this drawdown is likely to be driven by the careful pairing of kelp species with farming environment. Temporally, there was a noted increase in carbon content and a decline in nitrogen content from March to May for both species, consistent with known seasonal nutrient dynamics in coastal waters. Notably, differences in the carbon stable isotope signatures (δ13C) between the kelps may hint at variations in metabolic pathways and nutrient sourcing, particularly concerning the preferential assimilation of CO2 versus HCO 3 - , and highlight the need for further work on this topic for applied macroalgal research.


Assuntos
Aquicultura , Carbono , Kelp , Nitrogênio , Kelp/metabolismo , Nitrogênio/metabolismo , Nitrogênio/análise , Carbono/metabolismo , Carbono/análise , Alaska , Nutrientes/metabolismo , Nutrientes/análise , Phaeophyceae/metabolismo
3.
Mol Ecol ; 31(24): 6473-6488, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36200326

RESUMO

Coastal refugia during the Last Glacial Maximum (~21,000 years ago) have been hypothesized at high latitudes in the North Atlantic, suggesting marine populations persisted through cycles of glaciation and are potentially adapted to local environments. Here, whole-genome sequencing was used to test whether North Atlantic marine coastal populations of the kelp Alaria esculenta survived in the area of southwestern Greenland during the Last Glacial Maximum. We present the first annotated genome for A. esculenta and call variant positions in 54 individuals from populations in Atlantic Canada, Greenland, Faroe Islands, Norway and Ireland. Differentiation across populations was reflected in ~1.9 million single nucleotide polymorphisms, which further revealed mixed ancestry in the Faroe Islands individuals between putative Greenlandic and European lineages. Time-calibrated organellar phylogenies suggested Greenlandic populations were established during the last interglacial period more than 100,000 years ago, and that the Faroe Islands population was probably established following the Last Glacial Maximum. Patterns in population statistics, including nucleotide diversity, minor allele frequencies, heterozygosity and linkage disequilibrium decay, nonetheless suggested glaciation reduced Canadian Atlantic and Greenlandic populations to small effective sizes during the most recent glaciation. Functional differentiation was further reflected in exon read coverage, which revealed expansions unique to Greenland in 337 exons representing 162 genes, and a modest degree of exon loss (103 exons from 56 genes). Altogether, our genomic results provide strong evidence that A. esculenta populations were resilient to past climatic fluctuations related to glaciations and that high-latitude populations are potentially already adapted to local conditions as a result.


Assuntos
Kelp , Refúgio de Vida Selvagem , Canadá , Frequência do Gene , Variação Genética/genética , Filogenia
4.
Korean J Parasitol ; 60(5): 361-365, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36320114

RESUMO

We report a species of diplostomid fluke recovered from 3 carcasses of wild Korean raccoon dog, Nyctereutes procyonoides koreensis, in Korea. A total of 107 diplostomid flukes were recovered from the small intestines of Korean raccoon dogs, which were obtained from the Gangwon Wildlife Medical Rescue Center. Worms fixed with 10% neutral formalin were subjected to microscopic observation and those fixed in 70% ethanol were used for molecular genomic analysis. The worm was divided into 2 separate parts, forebody and hindbody, with a total length of 3,020-4,090 (3,855) µm and a width of 1,210-1,770 (1,562) µm. The boat-shaped forebody has a pair of characteristic tentacular appendage, 2 suckers, holdfast organ, and vitelline follicles. The oval to cylindrical hindbody has reproductive organs. The ovary was round or elliptical and located in the anterior of the testes. Two large testes were slightly segmented and tandemly arranged, occupying almost half of hindbody. The short uterus contained a relatively small number of unembryonated eggs sized 130-140×85-96 µm. The partial sequence of 18S rRNA of this fluke was consistent with Alaria alata. Based on the morphological and molecular characteristics, the diplostomid flukes recovered from the small intestine of Korean raccoon dogs were identified as A. alata (Digenea: Diplostomidae).


Assuntos
Cães Guaxinins , Trematódeos , Animais , Feminino , Animais Selvagens , Trematódeos/genética , República da Coreia , RNA Ribossômico 18S
5.
Mar Drugs ; 19(10)2021 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-34677439

RESUMO

Colorectal cancer is one of the most frequent types of malignancy in the world. The search for new approaches of increasing the efficacy of cancer therapy is relevant. This work was aimed to study individual, combined anticancer effects, and molecular mechanism of action of sulfated laminaran AaLs of the brown alga Alaria angusta and protolinckiosides A (PL1), B (PL2), and linckoside L1 (L1) of the starfish Protoreaster lincki using a 3D cell culture model. The 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS), soft agar, 3D spheroids invasion, and Western blotting assays were performed to determine the effect and mechanism of the action of investigated compounds or their combinations on proliferation, colony formation, and the invasion of 3D HCT 116 spheroids. AaLs, PL1, PL2, and L1 individually inhibited viability, colony growth, and the invasion of 3D HCT 116 spheroids in a variable degree with greater activity of linckoside L1. AaLs in combination with L1 exerted synergism of a combined anticancer effect through the inactivation of protein kinase B (AKT) kinase and, consequently, the induction of apoptosis via the regulation of proapoptotic/antiapoptotic proteins balance. The obtained data about the efficacy of the combined anticancer effect of a laminaran derivative of brown algae and polyhydroxysteroid glycosides of starfish open up prospects for the development of new therapeutic approaches for colorectal cancer treatment.


Assuntos
Antineoplásicos/farmacologia , Glucanos/farmacologia , Glicosídeos/farmacologia , Phaeophyceae , Estrelas-do-Mar , Animais , Antineoplásicos/química , Organismos Aquáticos , Proliferação de Células/efeitos dos fármacos , Sinergismo Farmacológico , Quimioterapia Combinada , Glucanos/química , Glicosídeos/química , Células HCT116/efeitos dos fármacos , Humanos
6.
Mar Drugs ; 19(12)2021 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-34940661

RESUMO

A growing concern for overall health is driving a global market of natural ingredients not only in the food industry but also in the cosmetic field. In this study, a screening on potential cosmetic applications of aqueous extracts from three Icelandic seaweeds produced by pulsed electric fields (PEF) was performed. Produced extracts by PEF from Ulva lactuca, Alaria esculenta and Palmaria palmata were compared with the traditional hot water extraction in terms of polyphenol, flavonoid and carbohydrate content. Moreover, antioxidant properties and enzymatic inhibitory activities were evaluated by using in vitro assays. PEF exhibited similar results to the traditional method, showing several advantages such as its non-thermal nature and shorter extraction time. Amongst the three Icelandic species, Alaria esculenta showed the highest content of phenolic (mean value 8869.7 µg GAE/g dw) and flavonoid (mean value 12,098.7 µg QE/g dw) compounds, also exhibiting the highest antioxidant capacities. Moreover, Alaria esculenta extracts exhibited excellent anti-enzymatic activities (76.9, 72.8, 93.0 and 100% for collagenase, elastase, tyrosinase and hyaluronidase, respectively) for their use in skin whitening and anti-aging products. Thus, our preliminary study suggests that Icelandic Alaria esculenta-based extracts produced by PEF could be used as potential ingredients for natural cosmetic and cosmeceutical formulations.


Assuntos
Antioxidantes/farmacologia , Produtos Biológicos/química , Cosmecêuticos/química , Extratos Vegetais/farmacologia , Alga Marinha , Antioxidantes/química , Organismos Aquáticos , Humanos , Islândia , Extratos Vegetais/química
7.
Parasitol Res ; 120(1): 83-91, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33103216

RESUMO

Alaria alata is a trematode included among several emerging zoonotic parasites. The mesocercarial larval stage of A. alata named Distomum musculorum suis (DMS) may potentially be infective for humans. In the past, DMS was often observed in wild boar meat during the official Trichinella inspection by artificial digestion before a more specific and effective detection method, the A. alata mesocercariae migration technique (AMT), was introduced. In the present study, the AMT method was used to screen 3589 tissue samples collected from wild boars hunted in Poland during the 2015-2019 period. The survey mainly focused on the southern part of Poland with the majority of samples coming from Malopolskie, Swietokrzyskie, and Dolnoslaskie provinces; samples from ten additional provinces were also included. The total prevalence was 4.2% with mean abundance of 4.7 DMS. Occurrence was dependent upon environmental conditions (i.e., wetland habitats and water reservoirs) rather than on sex of the host or season in which they were hunted. The recovered trematodes were identified as Alaria spp. according to their morphological features. Molecular analysis of 18S rDNA and COI genes confirmed the species identification to be A. alata and documented genetic variability among the isolates.


Assuntos
Sus scrofa/parasitologia , Doenças dos Suínos/epidemiologia , Trematódeos/classificação , Trematódeos/genética , Animais , Complexo IV da Cadeia de Transporte de Elétrons/genética , Humanos , Larva/patogenicidade , Carne/parasitologia , Polônia/epidemiologia , Prevalência , RNA Ribossômico 18S/genética , Suínos , Doenças dos Suínos/parasitologia , Trematódeos/isolamento & purificação
8.
Parasitol Res ; 120(6): 2103-2108, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33963900

RESUMO

Since 2002, Alaria (A.) alata mesocercariae (AM) have been found during routine Trichinella inspection of wild boars in many European countries. To date, human infection with AM through consumption of undercooked or raw AM infested wild boar meat cannot be excluded. In Germany, data on the parasite's prevalence in wild boars are scarce. To better understand temporal and spatial fluctuations of this parasite, this study investigated the prevalence of AM in wild boars in the German federal state of Brandenburg during three hunting seasons from 2017 to 2020. In total, 28.3% (100/354, 95% CI: 23.3-33.3%) of all wild boars sampled in eight counties of Brandenburg were tested positive for AM by Alaria alata mesocercariae migration technique (AMT). AM were detected in wild boars from seven different counties. Samples from one county (Havelland) tested completely negative for AM (0/16). Prevalences of the seven AM positive counties of Brandenburg ranged from 11.5 (3/26, 95% CI: 2.5-30.1%) in Märkisch-Oderland to 64.1% (25/39, 95% CI: 47.2-78.8%) in Uckermark. An association between sex and A. alata positivity could not be determined. A statistically significant increase in frequency of older AM positive wild boars was observed (p = 0.001). For a nationwide assessment of the prevalence of A. alata in wild boars and the risk for consumers of ingesting viable AM by consumption of raw or undercooked AM infested wild boar meat, further long-term studies in different regions of Germany are needed.


Assuntos
Sus scrofa/parasitologia , Trematódeos/isolamento & purificação , Animais , Parasitologia de Alimentos , Alemanha/epidemiologia , Humanos , Carne de Porco/parasitologia , Prevalência
9.
Korean J Parasitol ; 57(6): 567-573, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31914506

RESUMO

An archaeoparasitological analysis of the soil samples from Nadym Gorodok site of Western Siberia has been carried out in this study. The archaeological site was dated as the 13 to 18th century, being characterized as permafrost region ensuring good preservation of ancient parasite eggs. Parasite eggs as Opisthorchis felineus, Alaria alata, and Diphyllobothrium sp. were found in the archaeological soil samples, which made clear about the detailed aspects of Nadym Gorodok people's life. We found the Diphyllobothrium sp. eggs throughout the 14 to 18th century specimens, allowing us to presume that raw or undercooked fish might have been commonly used for the foods of Nadym Gorodok inhabitants and their dogs for at least the past 400 years. Our study on Nadym Gorodok specimens also demonstrate that there might have been migratory interactions and strong economic ties between the people and society in Western Siberia, based on archaeoparasitological results of Opisthorchis felineus in Western Siberia.


Assuntos
Opisthorchis/isolamento & purificação , Parasitologia/história , Solo/parasitologia , Animais , Arqueologia/história , Diphyllobothrium/classificação , Diphyllobothrium/isolamento & purificação , História do Século XV , História do Século XVI , História do Século XVII , História do Século XVIII , História Medieval , Humanos , Platelmintos/classificação , Platelmintos/isolamento & purificação , Sibéria
10.
Parasitol Res ; 117(4): 1297-1299, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29502296

RESUMO

Alaria spp. mesocercariae are commonly found in wild boar and other omnivorous mammals. In Europe, the number of cases presenting Alaria mesocercariae infections has been on the rise in the last years. From October to December 2016, samples of muscle from tongue, neck, and mandibular regions were collected from 1 Eurasian badger (Meles meles) and 14 wild boars (Sus scrofa) hunted in the Bialowieza Forest, north-eastern Poland. Using the Alaria migration technique (AMT), Alaria mesocercariae were isolated and morphologically identified in one badger and one wild boar. To the authors' knowledge, this is the first report of Alaria mesocercariae in paratenic hosts from the Bialowieza Forest.


Assuntos
Músculos/parasitologia , Mustelidae/parasitologia , Sus scrofa/parasitologia , Suínos/parasitologia , Trematódeos/isolamento & purificação , Animais , Feminino , Florestas , Humanos , Masculino , Polônia , Trematódeos/classificação
11.
Parasitol Res ; 117(7): 2207-2215, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29748713

RESUMO

Wild boar is a source of human infections with zoonotic pathogens, including food-borne parasites. With the aim of a characterization of the human exposure risk, a survey on wild boars intended for human consumption was planned, selecting three pathogens, Toxoplasma gondii, Alaria alata, and Trichinella spp., as markers of meat infection. Diaphragm muscle samples from 100 wild boars hunted in Piedmont region (Northern Italy) in two hunting seasons (2015-2016) were collected. Concerning T. gondii, a combined approach of antibody detection and molecular techniques with genotyping was performed. For the detection of A. alata and Trichinella spp., the larva migration technique and the magnetic stirrer method were employed, respectively; in addition, molecular confirmation of the morphological identification of the recovered specimen was performed. Anti-T. gondii antibodies were found in meat juice samples (43.3%) and T. gondii DNA (type II) was detected in three animals (7.1%) out of 42 seropositive examined. In none of the sampled wild boars (0%), Trichinella spp. larvae were found, whereas one animal (1%) scored positive to A. alata mesocercariae. The molecular diagnosis proved the morphological identification of the trematode. This is the first finding of A. alata in Italian wild boar population. The present study confirmed the role of wild boars as a source of parasitic zoonotic diseases and thus the risk derived for humans posed by the consumption of game meat. Considering the zoonotic implications, the results underline the importance of monitoring and surveillance of zoonotic parasites in Italian wild boar populations.


Assuntos
Doenças Transmitidas por Alimentos/epidemiologia , Carne/parasitologia , Toxoplasma/isolamento & purificação , Trematódeos/isolamento & purificação , Trichinella/isolamento & purificação , Animais , Anticorpos Antiprotozoários/sangue , DNA de Protozoário/genética , Feminino , Doenças Transmitidas por Alimentos/parasitologia , Humanos , Itália/epidemiologia , Larva , Masculino , Sus scrofa/parasitologia , Suínos , Doenças dos Suínos/parasitologia , Toxoplasma/genética , Toxoplasma/imunologia , Trichinella/classificação , Zoonoses/epidemiologia
12.
Parasitol Res ; 117(12): 3743-3751, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30218314

RESUMO

The trematode Alaria alata has a complex life cycle in which carnivore mammals may become infected by feeding on mesocercariae-infected, second intermediate hosts or paratenic hosts. Afterwards, young flukes migrate through various organs of the definitive host, including the diaphragm and the lungs, before reaching the small intestine. The aim of the present study was to establish the prevalence and infection intensity of A. alata in carnivore mammals, the host age and related occurrence of different A. alata development stages in particular animals in Latvia. Overall, samples from 992 animals (539 red foxes, 411 raccoon dogs and 42 grey wolves) were examined using sedimentation and counting techniques to observe the presence of A. alata metacercariae and adult trematodes in each particular host. The present study, based on data collected over five hunting seasons (2010/2011-2014/2015), is a comprehensive study on the circulation of A. alata in wild canids in Latvia. A. alata was present in all species examined and the overall prevalence reached 86.2%. A significant positive correlation was observed between the burden of A. alata metacercariae and adult trematodes in raccoon dogs (rs = 0.27, p = 0.001) and red foxes (rs = 0.17, p = 0.0002). A significantly higher (p = 0.003) A. alata metacercariae mean intensity was observed in juvenile raccoon dogs compared to the one observed in adult raccoon dogs and red foxes from both age groups. The presence of both A. alata development stages in a particular animal concurrently and at different intensity levels may indicate primary infection and re-cured infection of the host.


Assuntos
Raposas/parasitologia , Cães Guaxinins/parasitologia , Trematódeos/isolamento & purificação , Infecções por Trematódeos/epidemiologia , Infecções por Trematódeos/veterinária , Lobos/parasitologia , Fatores Etários , Animais , Letônia/epidemiologia , Carga Parasitária , Densidade Demográfica , Prevalência , Infecções por Trematódeos/parasitologia
13.
Parasitol Res ; 116(4): 1411-1416, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28229221

RESUMO

The neozoan species raccoon dog (Nyctereutes procyonoides) and raccoon (Procyon lotor) are widespread in Europe and potential vectors of many diseases that can threaten human and domestic animal health. Facing a further spread of these species, it is important to know about (i) pathogens imported and/or (ii) pathogens acquired in the new habitat. Thus, we investigated the parasite fauna of wild raccoon dogs and raccoons from Austria, at the edge of their new distribution range. The eight examined raccoons were nearly free of pathogens including Baylisascaris procyonis, and thus assumed to have a low epidemiological impact, so far. Out of ten raccoon dog specimens, we found one from western Austria to be infected with Echinococcus multilocularis and another three from the eastern wetland regions to harbour adults of Alaria alata. Furthermore, we detected Babesia cf. microti in five of eight raccoon dogs all over Austria but none of our samples were tested positive for Trichinella spp. Nevertheless, the raccoon dog seems to be a relevant host, at least for the zoonotic pathogens E. multilocularis and A. alata, and we suggest to further monitor the raccoon dogs parasite fauna.


Assuntos
Ascaridoidea , Reservatórios de Doenças/veterinária , Echinococcus multilocularis , Cães Guaxinins/parasitologia , Guaxinins/parasitologia , Zoonoses/parasitologia , Animais , Infecções por Ascaridida/epidemiologia , Infecções por Ascaridida/parasitologia , Infecções por Ascaridida/veterinária , Áustria/epidemiologia , Equinococose/epidemiologia , Equinococose/parasitologia , Equinococose/veterinária , Humanos
14.
Parasitol Res ; 114(12): 4451-61, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26337267

RESUMO

Trematodes of the genus Alaria develop into an arrested stage, known as mesocercariae, within their amphibian second intermediate host. The mesocercariae are frequently transmitted to a non-obligate paratenic host before reaching a definitive host where further development and reproduction can occur. Snakes are common paratenic hosts for Alaria spp. with the mesocercariae often aggregating in the host's tail. In the current study, we used morphological examination and molecular analyses based on partial sequences of nuclear large ribosomal subunit gene and mitochondrial cytochrome C oxidase subunit 1 gene to identify larvae in the tails of red-sided garter snakes (Thamnophis sirtalis parietalis) as mesocercariae of Alaria marcianae, Alaria mustelae, and Alaria sp. as well as metacercariae of Diplostomidae sp. of unknown generic affiliation. We assessed infection prevalence, absolute and relative intensity, and associated pathological changes in these snakes. Infection prevalence was 100 % for both male and female snakes. Infection intensity ranged from 11 to more than 2000 mesocercariae per snake tail but did not differ between the sexes. Gross pathological changes included tail swelling while histopathological changes included mild inflammation and the presence of mucus-filled pseudocysts surrounding mesocercariae, as well as the compression and degeneration of muscle fibers. Our results indicate that mesocercariae can lead to extensive muscle damage and loss in both sexes which likely increases the fragility of the tail making it more prone to breakage. As tail loss in garter snakes can affect both survival and reproduction, infection by Alaria mesocercariae clearly has serious fitness implications for these snakes.


Assuntos
Infecções por Cestoides/veterinária , Colubridae/parasitologia , Platelmintos/fisiologia , Animais , Infecções por Cestoides/parasitologia , Feminino , Larva/crescimento & desenvolvimento , Larva/fisiologia , Masculino , Platelmintos/crescimento & desenvolvimento , Cauda/parasitologia
15.
Parasitol Res ; 114(12): 4405-12, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26319522

RESUMO

In the last 15 years, the mesocercariae of Alaria alata have frequently been reported in the wild boar during routine Trichinella inspections made compulsory for the trade of venison meat in Europe. If these studies have focused primarily on mesocercariae isolated from meat, few works have been done so far to understand the circulation of the parasite in natural conditions especially in the intermediate hosts. This study focuses on the second intermediate hosts of this parasite assessing the suitability of two amphibian groups-brown frogs and water frogs sensu lato-for mesocercarial infection on an area where A. alata has already been identified in water snails and wild boars. During this study, both groups showed to be suitable for mesocercarial infection, with high prevalence and parasite burdens. Prevalence was higher in the brown frog group (56.9 versus 11.54 % for water frogs) which would indicate that it is a preferential group for infection on the study area, though reasons for this remain to be investigated. No significant difference among prevalences was observed between tadpoles and frogs. This study, the first focusing on A. alata in these amphibians in Europe, provides further information on circulation of this parasite in natura.


Assuntos
Carne/parasitologia , Platelmintos/isolamento & purificação , Ranidae/parasitologia , Animais , Europa (Continente) , Larva/parasitologia , Platelmintos/classificação , Platelmintos/genética , Platelmintos/fisiologia , Prevalência , Trichinella/genética , Trichinella/isolamento & purificação , Trichinella/fisiologia
16.
Carbohydr Polym ; 325: 121557, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38008481

RESUMO

Alginates are valued in many industries, due to their versatile properties. These polysaccharides originate from brown algae (Phaeophyceae) and some bacteria of the Azotobacter and Pseudomonas genera, consisting of 1 â†’ 4 linked ß-d-mannuronic acid (M), and its C5-epimer α-l-guluronic acid (G). Several applications rely on a high G-content, which confers good gelling properties. Because of its high natural G-content (FG = 0.60-0.75), the alginate from Laminaria hyperborea (LH) has sustained a thriving industry in Norway. Alginates from other sources can be upgraded with mannuronan C-5 epimerases that convert M to G, and this has been demonstrated in many studies, but not applied in the seaweed industry. The present study demonstrates epimerisation directly in the process of alginate extraction from cultivated Saccharina latissima (SL) and Alaria esculenta (AE), and the lamina of LH. Unlike conventional epimerisation, which comprises multiple steps, this in-process protocol can decrease the time and costs necessary for alginate upgrading. In-process epimerisation with AlgE1 enzyme enhanced G-content and hydrogel strength in all examined species, with the greatest effect on SL (FG from 0.44 to 0.76, hydrogel Young's modulus from 22 to 34 kPa). As proof of concept, an upscaled in-process epimerisation of alginate from fresh SL was successfully demonstrated.


Assuntos
Laminaria , Phaeophyceae , Alginatos , Hidrogéis
17.
Pathogens ; 13(6)2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38921788

RESUMO

The aim of the study was to determine the species composition of the intestinal parasite fauna of foxes from the Pomerania region, with a particular emphasis on helminth species considered dangerous to humans, and to determine their prevalence and intensity of infection. In total, 165 digestive systems from foxes inhabiting the Pomeranian region were examined. The prevalence of intestinal parasites among the studied foxes was 61.8%. Our findings confirm that foxes in Pomerania carry various parasites, some of which pose a direct threat to human health. As such, constant monitoring of their infestation is essential. Particular attention should be paid to parasite species with potential for transmission to humans, such as Echinococcus multilocularis, Alaria alata and Toxocara canis, whose respective prevalence was found to be 10.9%, 17.6% and 28.5%.

18.
Int J Biol Macromol ; 229: 199-209, 2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36584780

RESUMO

Fucoidans are fucose rich sulfated polysaccharides that are found in the cell wall of brown seaweeds and have been shown to have several beneficial bioactivities. In the present study, we report a new enzymatic extraction technique for the production of pure and intact fucoidans from the two brown seaweeds Saccharina latissima and Alaria esculenta. This new extraction protocol uses the commercial cellulase blend Cellic® CTec2 in combination with endo- and exo-acting thermophilic alginate lyases. The fucoidans obtained by this extraction technique are compared to traditionally extracted fucoidans in terms of chemical compositions and molecular weights and are shown to contain significantly higher amounts of fucose and sulfate, the main components of fucoidans, while cellulose, laminarin, and alginate contamination is low. Thus, by using this combination of enzymes, the extracted fucoidans do not undergo depolymerization during extraction and additional purification steps are not needed. The high purity fucoidans isolated by this new enzymatic extraction technique can be used to provide insight into the different fucoidan structures and biological activities.


Assuntos
Celulases , Phaeophyceae , Alga Marinha , Fucose/química , Polissacarídeos/química , Alga Marinha/química , Phaeophyceae/química , Alginatos
19.
Int J Biol Macromol ; 225: 648-657, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36395953

RESUMO

Six fucoidan fractions were isolated from the brown alga Alaria angusta. Structures of enzymatic hydrolysis products of the fraction 1AaF2 (Fuc:Gal ~ 1:1; 33 % of sulfates) by fucanase from Wenyingzhuangia fucanilytica were studied by chemical and instrumental (NMR spectroscopy and mass-spectrometry) methods. It was shown that 1AaF2 consisted of two structurally different fucoidans: a sulfated 1,3;1,4-α-L-fucan and an enzyme-resistant sulfated and acetylated complex fucogalactan (Fuc:Gal ~ 1:2; 19 % of sulfates) 1AaF2_HMP containing extended 1,3-linked fucose and 1,3/1,4-linked galactose fragments (up to 5 residues). The fractions 1AaF2 and 1AaF2_HMP were a non-cytotoxic, possessed dose-dependent chemopreventive effect on EGF-induced neoplastic cell transformation of mouse normal epidermal JB6 Cl41 cells and inhibited the colony formation of human melanoma SK-MEL-28 cells.


Assuntos
Antineoplásicos , Melanoma , Phaeophyceae , Animais , Camundongos , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/química , Polissacarídeos/farmacologia , Polissacarídeos/química , Phaeophyceae/química , Sulfatos/química
20.
Int J Parasitol Parasites Wildl ; 17: 257-262, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35309038

RESUMO

Alaria alata is an emerging parasite that poses a potential risk for those consuming game, pork, snails and frogs. One paratenic host of A. alata that is known to play an important role in its spread through its feeding habitats is the wild boar. However, no statistical analysis of the influence of aquatic environments and carnivores on the occurrence of A. alata in wild boars has yet been performed. The present study combines a small-scale analysis based on hunting districts in the Mazowieckie province with a large-scale analysis based on data for all provinces in Poland. We applied various modeling approaches, including logistic regression and a generalized linear model in order to determine the presence, intensity and prevalence of A. alata. We used the Alaria mesocercariae migration technique (AMT) to estimate the risk of A. alata among wild boar in a given hunting district or province. The small-scale analysis found that mesopredators (red fox (Vulpes vulpes)) and racoon dog (Nyctereutes procyinoides) were likely to influence A. alata infestation of wild boar; however, the effect was weak, probably as a result of the large home range size of these animals. The large-scale analysis found that wetlands influence the prevalence of A. alata in wild boar, with the estimated risk increasing in the north of the country; this finding is consistent with other studies. Our findings indicate that the occurrence of A. alata in wild boar requires analysis on many levels, and environmental factors play a key role in risk assessment.

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